Chap 2 HISTORY OF LIFE The Geological Record: Relative ages from Stratigraphy Layered rocks in Bryce Canyon, Utah, formed by solidification of sediments laid down sequentially over millions of years. Paleontologists reconstruct the Earth’s biological and geological history by analyzing the fossils and minerals found in different layers, and by determining the ages of different layers using radiocarbon and other methods of dating. Bryce Canyon, Utah (布萊斯峽谷)

San Onofre: Stratigraphy Newer Alluvial sediments: recent Marine Boulder Bed 125,000 yr. San Mateo Formation 5 m.yr. Cliffs at San Onofre in Orange County show the same kind of layering 南加地區為數不多的裸體海灘之一，位於聖地牙哥縣北部，與橙縣交界的San Onofre的海灘，目前面臨『禁止裸露』的要求，有民眾索性在海灘裸體抗議。 Older San Onofre: Stratigraphy

Absolute ages from Radiocarbon dating radioactive 7N; 7P 8N; 6P radioactive http://www.earthsci.org/geotime/radate/radate.html 8N; 6P 7N; 7P Neutron turns into a proton by emitting an antineutrino and a beta particle (Useful to ~60,000 years) Other dating methods using decay of other isotopes: Uranium-lead: 1 million years to over 4.5 billion years Potassium-argon: >100 million years

544 Origin of life Plants, invertebrates, first vertebrates PRECAMBRIAN PALEOZOIC MESOZOIC CENOZOIC Origin of life Plants, invertebrates, first vertebrates Reptiles, Flowering plants Mammals ERAs Fish Geological Time and the rise of biological diversity The chart shows the number of families of marine organisms on the earth at different times in biological history. It represents only marine animals since the ocean is where life started, and marine animals are the best represented in the fossil record. See Measuring Past Biodiversity, by Jeremy B. C. Jackson and Kenneth G. Johnson.  Science 2001 September 28; 293: 2401-2404. [Summary] [Full Text] [Supplemental Data] Four eras are recognized and divided into periods. They are characterized by typical life forms: 1. Precambrian: The origin of life. 2. Paleozoic ("Ancient Life"):  The origin of plants, most invertebrate types, the first vertebrates (back-boned animals, including fishes, amphibians, and reptiles). Multicellular animals first appeared about 600 million years ago in the early Paleozoic and there was a rapid rise in number of families during the Cambrian and Ordovician. Diversity remained relatively constant (perhaps even declining) up until about 200 million years ago. 3. Mesozoic (the "Age of Reptiles"): The origin of flowering plants, dinosaurs, birds, and mammals. Number of families rising. 4. Cenozoic (the "Age of Mammals"): The diversification of flowering plants, insects, birds and mammals, and the appearance of humans. The number of families rose to its current all-time high of close to 800. Biological diversity was dramatically depleted by five mass extinction episodes at the ends of the Ordovician, Devonian, Permian, Triassic and Cretaceous Periods. At each of these times a large fraction of existing species was wiped out, leaving the survivors to repopulate the biological world. The most famous of these was the extinction at the end of the Cretaceous because this ended the age of dinosaurs and made possible the evolution and dominance of mammals. But it was not the most devastating of the mass extinctions.  544

Eukaryotes: DNA in a nucleus Prokaryotes: DNA not in a nucleus

Permian 二疊紀 Carboniferous泥炭紀 Devonian Permian 二疊紀 Carboniferous泥炭紀 Devonian? Silurian志留紀Ordovician 奧陶紀Cambrian 寒武紀

Cretaceous石炭紀 Jurassic侏羅紀 Triassic 三疊紀

Quaternary 第三紀 Tertiary 第四紀

Permian 二疊紀 Carboniferous Devonian泥炭紀 Permian 二疊紀 Carboniferous Devonian泥炭紀? Silurian志留紀Ordovician 奧陶紀Cambrian 寒武紀

Burgess Shale fossils (Cambrian) ~530 million years old Burgess Shale 柏吉斯頁岩從加拿大洛磯山柏吉斯山頁岩明顯包含中寒武紀( 距今5.2～5.12億年)的軟體生物群的細緻痕跡的化石岩層。這處全世界最著名且最豐富的化石層中， 有一百二十種海洋生物的 化石，考其年代，可上溯五億三千萬年前，堪稱是地球上最寶貴 的生物資產之一。大英百科全書線上繁體中文版大英百科全書線上繁體中文版 tw.britannica.com/MiniSite/Article/id00010074.html The Walcott Quarry, Yoho National Park, British Columbia, Canada.

Hallucigenia環節動物 Hallucigenia appears in early reconstructions as walking on its spines, a bizarre characteristic shared with no other animal. Recent discoveries of related fossils in China, however, indicate that it is an ancestor to modern Onychophora, animals of temperate and tropical rainforests, and that the spines were defensively oriented along its back. http://members.aol.com/kbclark/cambrian/index.html Hallucigenia環節動物

Marrella splendens (卓越馬瑞拉蟲) is the commonest fossil from the Burgess Shale. The extensive gill development, in an animal of only 2 cm length, suggests that oxygen levels in Cambrian seas were low enough to require extensive investment in respiratory organs. Marrella: Lace Crab

Wiwaxia奇虾类

Opabinia with its five large stalked eyes Opabinia, with its five large stalked eyes, is distinctly different from all living animals.Here, I interpret Opabinia as a roving benthic predator, with the paddle-like legs serving both as gills and as swimmerets, allowing the animal to hover near the bottom of the sea floor, probably in near-darkness, using its well-developed eyes to visually search the bottom and near-bottom waters for a variety of prey. (c) k b clark 1994 Opabinia with its five large stalked eyes

Amiskwia: Primitive Arrow-worm? © Kerry B. Clark 1994 Amiskwia shared general shape and paired, rayed-fins with modern chaetognaths (arrow-worms), and may represent their ancestors. This would imply evolution from placid detrital browsers (Amiskwia) to rapid, venomous pursuit predators, the arrow-worms.

Dinomischus足杯虫 Authorities on the Burgess Shale fauna believe that Dinomischus is not closely related to any existing phylum, but there are some similarities to a group of suspension-feeding phyla called the lophophorates. In this interpretation, the vanelike bracts may have analogy to the softer, unskeletalized tentacular arms of modern entoprocts. (c) k b clark 1994

Priapulid: (三部蟲門 ) early carnivore Priapulids are common among Cambrian fossils, though today they are few in species, and limited mostly to colder seas and the interstitial fauna. Early priapulids probably burrowed in pursuit of other worms, much as the living priapulids do today. (c) k b clark 1994

Anomalocaris寒武紀的巴傑斯動物群之一 Anomalocaris canadensis is the largest fossil from the Burgess Shale, reaching about a half meter in length. Though generally interpreted as a herbivore, we portray Anomalocaris here as a herding algal herbivore, with the anterior appendages used for collection of algal filaments. (c) 1996 by k b clark Anomalocaris寒武紀的巴傑斯動物群之一

Carboniferous 石炭紀三億六千萬年前

Carboniferous: 360-286 million years ago

Giant (14-inch wing span) mayfly-like “six-winged” insect (Paleodictyoptera) from the Carboniferous

2 cm Giant Dragonfly from the Carboniferous (Some species had 30 inch wing span!)

Permian 二億八千萬年前(二疊紀)

Permian: 286-245 million years ago

Permian: 286-245 million years ago

Mammal-like reptiles

: Flood volcanism in Siberia? Mass extinction at the end of the Permian (245 million years ago) Disappearing: 96% of all marine animal species 8 of 27 orders of insects 21 of 27 families of reptiles 6 of 9 families of amphibians most of the terrestrial plant life : Flood volcanism in Siberia? Flood volcanism 火山活動大規模噴發的大陸洪流玄武岩 to be checked ?

Triassic: 245-208 million years ago: first true mammals 三疊紀Triassic Period, 距今2.2~1.9億年的地質年代 Triassic: 245-208 million years ago: first true mammals

New evidence?

Lizard-hips Bird-hips Jurassic and Cretaceous: 208-65 million years ago: the Age of Dinosaurs

Bird-hip dinosaurs Pterosaurs翼龍 Sauropelta 蜥結龍 Sauropods 蜥腳亞目 Scelidosaurus 稜背龍 Segnosaurischia 慢龍目恐龍 Segnosaurus 慢龍 Seismosaurus 地震龍 Shamosaurus 沙漠龍 Shantungosaurus 山東龍 Spinosaur 棘龍科 Spinosaurus 棘龍 Stegoceras 頂角龍 Stegosaurs 劍龍下目 Stegosaurus

Ankylosaurs甲龍 (bird-hip)

Stegosaurs劍龍 (bird-hip)

Ceratopsians角龍 – Pentaceratops五角龍(Bird-hip)

Sauropods 長尾巴蜥腳類動物（sauropods） (lizard-hip)

Sauropods (lizard-hip)

Homo Atlantosaurus 阿特拉斯龍-----1878年命名，根據發掘Atlas而來。侏羅紀晚期。發掘於美國科羅拉多州。屬於蜥腳類之梁龍科（？）。體長可達23公尺。有些後來歸於迷惑龍。鑑定存疑。.

Therapods (lizard-hip)

Pterosaurs Pterosaurs翼龍 Ichthyosaurs魚龍

Quetzalcatlus northropi: 40 foot wing span

Archaeopteryx

Cycads蘇鐵目 : the first flowering plants Female cone Male cone